In downhill speed skiing a skier is retarded by both the air drag force on the body and the kinetic frictional force on the skis. Suppose the slope angle is 0 = 42.0°, the snow is dry snow with a coefficient of kinetic friction UK = 0.0410, the mass of the skier and equipment is m = 87.0 kg, the cross-sectional area of the (tucked) skier is A = 1.40 m², the drag coefficient is C = 0.180, and the air density is 1.20 kg/m³. (a) What is the terminal speed? (b) If a skier can vary C by a slight amount dC by adjusting, say, the hand positions, what is the corresponding variation in the terminal speed? Give your answer in terms of the given values and dC (need derivative for given values). (a) Number 60.4 (b) Number i Units m/s dC Units ♦

In downhill speed skiing a skier is retarded by both the air drag force on the body and the kinetic frictional force on the skis. Suppose the slope angle is 0 = 42.0°, the snow is dry snow with a coefficient of kinetic friction UK = 0.0410, the mass of the skier and equipment is m = 87.0 kg, the cross-sectional area of the (tucked) skier is A = 1.40 m², the drag coefficient is C = 0.180, and the air density is 1.20 kg/m³. (a) What is the terminal speed? (b) If a skier can vary C by a slight amount dC by adjusting, say, the hand positions, what is the corresponding variation in the terminal speed? Give your answer in terms of the given values and dC (need derivative for given values). (a) Number 60.4 (b) Number i Units m/s dC Units ♦

University Physics Volume 1

18th Edition

ISBN:9781938168277

Author:William Moebs, Samuel J. Ling, Jeff Sanny

Publisher:William Moebs, Samuel J. Ling, Jeff Sanny

Chapter6: Applications Of Newton's Laws

Section: Chapter Questions

Problem 81P: A 560-g squirrel with a surface area of 930cm2falls from a 5.0-m tree to the ground. Estimate its...

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